Process and apparatus for the production of rubber filaments or threads



Mar. 3, 1925. 1,528,537

" M. DRAEMANN PROCESS AND APPARATUS FOR THE PRODUCTION OF RUBBER FILAMENTS OR THREADS Filed Aug. 16, 1922 Patented Mar. 3, 1925.

UNITED STATES PATENT OFFICE.

MAX DRAEMANN. OF COLOGNE, GERMANY.

PROCESS AND APPARATUS FOR THE PRODUCTION OF RUBBER FILA'MIENTS R THREADS. I

Application filed August 16, 1922. Serial No. 582,211.

T!) all tUll-OHL if may concern Be it known that 1, MAX DmumANN, citizen of Germany, residing at Cologne, Germany, have invented new and useful Improvenients in Processes and Apparatus for the Production of Rubber Filaments or Threads, of which the following is a specification.

lhe present invention relates to a method by which rubber filaments of round section may be produced in a commercially and technically practicable manner, and apparatus therefor.

The invention consists in that the round filaments issuing from a-press are led. after evaporation of the solvent continuously through molten "sulphur thereby being quickly vulcanized. On leaving the sulphur bath the filaments are at once coiled up into desired lengths or removed in any other convenient manner. The rubber paste can be mixed with about 10% of sulphur, so that as soon as the filaments enter the sulphur bath the vulcanizing process begins, for by virtue of the small section of the filaments, they assume immediately the temperature of the bath, so that the vulcanizing time is appreciably shortened. The liquid sulphur is heated to a temperature of about 130 C. Immediately on leaving the vulcanizing bath the finished filaments can be coiled up or otherwise removed. A continuous process is therefore possible and filaments of any desired length can be produced. In contradistinction to processes previously employed, in which filaments of square section were cut from slabs, the new method permits a reduction of the working costs of something like a third.

In the drawing, one method of employing the new arrangement is shown diagrammatically. From the draw press 6, operated by the hydraulic press a, the rubber filanients o from fine holes, emerge and are delivered on to anendless conveyor belt d. After passing the drying device 6 where the benzine is evaporated, they are carried by the belt into the bath 7 filled with molten sulphur, or other suitable liquid. Above the conveyor belt d but in the liquid, runs an other endless belt 9. Since the rubber filaments are lighter than the liquid sulphur, they rest, because of their buoyancy, against the upper belt g, which is moving at exactly the same speed as the lower one. By virtue of the present invention, this disadvantage is removed without ditficulty in that the liquid layer which lies between the two su- I per-posed conveyor belts d and 9 because of its viscosity, partakes of their movement, and hence has no velocity relative to the filaments. Furthermore, this effect may be increased by adding chains, projections or other suitable devices at the sides of the conveyor belts.

The filaments themselves can consist, according to the choice of the vulcanizing agent, of pure rubber, or sulphur may be added to the mixture before their production Civhereb-y the vulcanizing process is as siste The upper conveyor belt 9 hangs in. the l liquid by its own weight or can be led round guide rollers or guideways in the liquid. Further, it may be employed in the liquid alone i. e. without the lower conveyor belt, since the rubber filaments in'the liquid will, by virtue of their buoyancy, rest against the gpper conveyor belt and be carried along In this case also. the viscous vulcanizing agent will be carried along withthe com veyor belt. and hence will be at rest relatively to the filaments.

Having now particularly described and ascertained the nature of my said invention and in what manner the same is to be per formed, I declare that what I claim is:

1. The process of producing rubber filaments, which consists in forming a solution of rubber, pressing said solution into filaments, evaporating the solvent from said filaments, and conducting said filaments throuoh a bath of liquid sulphur.

2. The process of producing rubberv filaments, which consists in forming a solution of rubber, pressing said solution into fila ments of round section, evaporating the solvent from said filaments, and conducting said filaments through a bath of liquid sulphur. I

3. The process of producing rubber filaments, which consists in forming a solution of rubber, pressing said solution into filaments evaporating the solvent from said filaments, and conducting said filaments through a bath of liquid sulphur the filaments being retained below the surface of the liquid during their passage through the bath.

4'. The process of producing rubber filaments, which. consists in forming a solution of rubber, mixing therein ten per cent, by weight of sulphur, pressing said solution into filaments of round section, evaporating the solvent therefrom, and conducting said filaments through a bath of liquid sulphur heated to a temperature of approximately 130.C. I

5. An apparatus for producing vulcanized rubber filaments of round section, comprising a press adapted to receive a rubber solution and deliver the same in the form of thread-like filaments, means for evaporating the solvent from said filaments immediately after their passage from the press and means for conducting the filaments from said evaporating means through a vulcanizing bath.

6. An apparatus for producing vulcanized rubber filaments comprising a press adapted to receive a rubber solution and deliver the same in the form of thread-like filaments,

rubber filament-s comprising a press adapted to receive a rubber solution and deliver the same in the form of thread-like filaments, means for evaporating the solvent from said filaments immediately after their passage from the press, a bath-containing receptacle contiguous to said evaporating means, and

a traveling belt to conduct the filaments from the press, through the evaporator and through and out of the bath.

8. An apparatus for producing vulcanized rubber filaments comprising a press adapted to receive a rubber solution and deliver the same in the, form of thread-like filaments, means for evaporating the solvent from said filaments immediately after their passage from the press. a bath-containing receptacle contiguous to said evaporating means, and a traveling belt to conduct the filaments from the press. through the evaporator and through and out of the bath, and a second belt traveling through the bath at a point just below its surface adapted to conduct the filaments through said bath as a result of the friction of the buoyant filaments against the under side of said belt.

In testimony whereof I have signed my name to this specification.

MAX DRAEMANN. 

